1. Field of the Invention
The present invention relates to a system for protecting data through backup and restore operations, and more particularly to backup and restore software for protecting data which is processed on a computer network
2. Description of the Related Art
In order to ensure that original data stored on a medium such as a disk is not lost or damaged, a copy of that data is stored on another medium. Should the original data be lost or damaged, then the copy may be accessed to reproduce the original data. This process of copying and reproducing is generally known as backup and restore. Typically, original data are stored on a hard or floppy disk of a computer disk drive and are backed up to and restored from tape media of a tape drive.
Backup and restore of the data are simple in a system that has a single standalone computer, having a given operating system and one or more disk drives, that interfaces with a tape drive system. A relatively simple backup and restore program can be used that interfaces with the computer operating system to backup data including files and directories stored on a hard disk to the tape drive and to restore such data from the tape drive onto the hard disk.
Computer networks have evolved and this has placed greater demands on backup and restore systems. A computer network may include a number of computers each with its own hard and/or floppy disk drive, all of which are networked together on a common bus. For example, the computers on the network may include one or more workstations and one or more file servers, each with its own hard disk drive. The file server may also have a tape drive upon which to backup and restore its own data as well as data stored on the disk drives of the workstations on the network. Backup and restore operations are still relatively simple for a computer network in which each workstation is running the same operating system or environment, such as that known as DOS. However, computer networks exist in which workstations and file servers on the network may be running disparate operating systems. For example, a computer network may have, or may be expanded to have, workstations running different operating systems including those known as DOS, Windows, OS/2, Macintosh, and UNIX. The computer network also may have, or may be expanded to have, file servers running networking operating systems software, including those known as NetWare, Lotus Notes, and LAN Manager.
In one particular example, a computer network having workstations and a file server running disparate operating systems may be supported by NetWare, which is an operating system made and sold by Novell, Inc. of Provo, Utah. NetWare is designed to manage the programs and data among several computers on a network, unlike, for example, DOS, which is an operating system for standalone personal computers. Novell also provides, for example, SBACKUP software, which is a NetWare Loadable Module (NLM) that can be loaded onto a NetWare file server to backup data to and restore data from a tape storage device attached to the NetWare server. SBACKUP has limited capabilities; for example, it is designed to backup and restore only NetWare server data and workstations running DOS, OS/2, and Windows.
The difficulty in providing backup and restore operations to protect data on a computer network obviously increases as more and more disparate operating systems are added to the network via the computers on which they run.
In general, prior backup and restore systems for computer networks are limited to the number of different types of operating systems that can be supported. This places expansion limitations on the network in terms of adding computers running additional types of operating systems. Also, these backup and restore systems do not have the capability of interchanging data between different operating systems. Furthermore, bottlenecks occur and productivity is limited with prior backup and restore operations since multiple users cannot simultaneously request these operations.